Method and equipment for restraining while knitting the end portions of cut thread protruding from collars for knit-wear articles and the like

ABSTRACT

A method and an apparatus, applicable to a knitting machine for the production of collars and the like, for restraining while knitting end portions of cut thread (12, 13) protruding from the edge (5) of said collars into the stitches that compose them. The means for introduction (16) of said thread ends (12, 13) among two next courses of stitches comprises fluid currents (22, 32) that catch the end portions and align them to the stitches while knitting. A combing step of the end portions and stretch them when passing may be provided for. A mobile blowing head (16) and a mobile nozzle (27) are provided for suited to produce said fluid currents (22, 32) while knitting and lower in order not to interfere with thread support means (8, 28). The and portions (12, 13) are restrained among the stitches of the collar without leaving portions or loops protruding from the edge. In order to make easier the separation of the collars, the thread of union of the collars is advantageously cut forming two thread ends which are restrained in turn among the stitches in the same way of the threads which form the collars.

DESCRIPTION

1. Field of the Invention

The present invention relates to the field of textiles and, moreprecisely, to a method for restraining the terminal portions of cutthread protruding from collars for knit-wear and similar articles byinserting them inside the stitches which compose the articles during thecourse of knitting. The invention relates also to a method for makingeasier the separation of collars after knitting.

The invention, furthermore, relates to an apparatus for carrying outsaid methods.

2. Description of the Prior Art

Collars used for making knit-wear articles are knitted in strips,attached in turn to one another along one common side by means ofprovisional stitches which can be eliminated pulling a thread of union.At the end of the knitting, and after a possible dyeing step, everycollar is attached to the previous and to the next not only by saidthread of union but also by the thread itself of the stitches forming aloop at the side of union. Each collar can be of a solid color orcomprise one or more bands of color, just as it can have multicolordesigns on a background color.

After separating the collars, it is necessary to insert the ends of thecut thread inside the stitches of thread that form the collar, so thatthey do not protrude from the collar disturbing its aesthetic value. Itis necessary to insert the end portions in the stitches in such a waythat they cannot easily come cut.

For collars of a solid color, the operation is carried out only once,since, of the two end portions of thread which protrude from eachcollar, one will be directly inserted into the stitches with which thecollar will be attached to the knit article.

On the other hand, when collars comprise more than one color, twoadditional ends of thread protrude from the edge for every color change.For example, for a collar having a band of color different from thebackground color, in the finishing steps, it will be necessary to insertfive thread ends (four for the two changes in color and one at the end),whereas for a collar with two bands of color different from thebackground, it will be necessary to insert nine thread ends (eight forfour color changes and one at the end).

The inserting step can be made manually, when the collars are finished,or automatically, while knitting.

The manual insertion, is carried out by inserting a special needleinside a portion of knitted collar until reaching the edge correspondingto the point from which the end portion of the thread extends. The endportion is then pulled inside the collar where it is restrained andhidden by the course of stitches forming the knit collar. This steprequires skill and the use of a special needle, and is expensive, inparticular when the collars present bands of color.

There is a known machine for the production of collars in which theoperation of inserting the ends of protruding thread is performed duringknitting by a mechanical needle. As the ends are produced, the needleinserts them between two successive courses of stitches, awaiting themoment of knitting to be withdrawn so that each end portion isrestrained inside. However, in order to prevent the needle, when itwithdraws, from dragging the thread end with it, pulling it newly out ofthe knitting, collars produced with this type of machine, have a tubularcourse of stitches which locally increases the thickness of the collarcreating a poor aesthetic effect. Furthermore, this type of mechanism iseven less appropriate when the knitting is very thin, since, in thiscase, the above-mentioned effect would be accentuated.

Another problem arises when separating the collars, in the steps ofcutting and pulling away the connecting thread. In fact, the cuttingstep of the connecting thread is critical if operated automatically,since it could result in a damage for the collars.

SUMMARY OF THE INVENTION

The object of the present invention is, therefore, to provide a methodfor inserting the ends of thread protruding from the edges of collarsand similar knit articles into the collar stitches, while knitting,which does not incur any of the above-mentioned inconveniences andwhich, at the same time, is simple to carry out.

It is another object of the present invention to provide a method forsimplifying the separation step of the collars and in particular thecutting step of the connecting thread.

It is further object of the present invention to provide an apparatuswhich carries out such method.

These and other objects are accomplished by the present invention, whosemethod is characterized by the fact that the step of catching andinserting the end of the thread occurs by means of at least one currentof fluid. After every insertion of a thread and in the stitches whileknitting, a stretching step of the thread end waiting to be restrainedin the stitches itself is provided for. The stretching step ispreferably carried out by means of a brush element that lowers on thethread and combing it while moving.

Preferably, two coplanar and orthogonally directed jets of a fluid, suchas air or water, are provided for. The first jet catches the thread endat the time of the cut and orients it in a direction which is notparallel to the knitting, whereas the second jet, which intervenes afterthe first, aligns the portion of thread with two consecutive courses ofstitches, so that they include it at the time of knitting the precedingand following ones.

Advantageously, one of the two jets of fluid accompanies the thread endby means of a rotation in said plane, from a position aligned with thefirst jet to a position aligned with the two ranks of stitches duringknitting.

In the case of knitting a first (collar with a first thread and then asecond collar with a second thread, the thread end of the first threadis advantageously sucked by a fluid current and aligned under thestitches while knitting, thereby the restraining step of the secondthread end can be carried out without that the first thread end isinvolved.

In order to make easier the separation of the collars, the thread ofunion is advantageously cut forming two thread ends which are restrainedin turn among the stitches in the same way of the threads which form thecollar.

The apparatus which carries out said method is characterised by the factthat it comprises at least one nozzle connected by means of the emissionof fluid under pressure and mobile brush means with actuator means thatlocate the brush means tangentially to said end portions combing themwhen moving. Preferably, it comprises two nozzles communicating with anetwork of compressed air through electro-valves.

According to a first advantageous embodiment, blowing means comprisingsaid nozzles are provided for mounted on actuator means that maintainsin lowered position while knitting and raises selectively at the sametime of the emission of air jets suited to catch said thread endportions.

Alternatively, according to a second advantageous solution, the secondnozzle is mounted on a rotatable support and can be oriented between twopositions in which the jet coming out of it is aligned respectively withthe jet of the first nozzle and with the two courses of stitches beingknitted. The first nozzle is positioned in proximity to the edge of theknit article in order to catch the protruding ends of thread immediatelyafter that they have been cut.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the method and the apparatusaccording to the present invention will become more apparent in thedescription which follows of some of its embodiments, given as anexample and not limitative, with reference to the attached drawings inwhich:

FIG. 1 shows a diagrammatic view of the steps according to the inventionof introduction by means of fluid currents of thread end portionsprotruding from the edge of a collar among consecutive courses ofstitches in case of change of color of the thread within a same collar;

FIG. 2 shows a diagrammatic view of the steps according to the inventionof introduction by means of fluid currents of thread ends protrudingfrom the edge of a second collar among consecutive courses of stitchesin the case of knitting a first collar and then knitting of a secondcollar;

FIG. 3 shows an elevational side view of a machine for collarscomprising an apparatus according to the invention;

FIG. 4 shows a front view of the machine of FIG. 3;

FIGS. 5, 6 and 7 show a lateral diagrammatic view of the restrainingsteps of a thread end in the stitches while knitting;

FIG. 8 shows a lateral diagrammatic view of the sucking steps of athread end under the stitches while knitting, in the case of knitting afirst collar and then a next one;

FIGS. 9, 10 and 11 show a partially sectioned view respectivelyelevational front, elevational lateral and top plan of a mobile head forthe emission of air jets;

FIG. 12 shows a partial elevational front view of a thread cutter

FIG. 13 shows a partial rear view of the machine of FIG. 3;

FIGS. 14 and 15 show a partial side view of two different embodiments ofthe machine of FIG. 3;

FIG. 15A is an enlarged view of the circled area in FIG. 15;

FIGS. 16A, B and C show three adjacent collars in three possiblearrangements after knitting.

DESCRIPTION OF PREFERRED EMBODIMENTS

In the case in which a change of color or the separation of two adjacentcollars is carried out while knitting, it is possible that whatdiagrammatically shown in FIGS. 1 and 2 occurs, with a first and asecond course of stitches indicated respectively with 2a and 2b, fromwhich extends, at the moment of thread change, a thread end 12. Theconsecutive courses of stitches, here illustrated separate from oneanother for the sake of clarity, are obviously, in reality, knittedtogether.

With reference to FIG. 1, in the passage from course 2b and a course 3a,when it is necessary to change a thread I into a thread II, for exampleof different color, free thread end 12 and 13 are formed, bothprotruding from the edge 5 of the stitches.

According to the present invention, end portions 12 and 13 areintroduced, while knitting, respectively among the courses of stitches2b and 3a and among the next courses of stitches 3b and 4a. The lettersa and b indicate respectively the courses of stitches knitted forth andback during the strokes of the carriage of the knitting machinedescribed hereinafter.

More precisely, with the numerals of FIG. 1, course 2a is knitted fromleft to right and then, with the same thread I of course 2b, from rightto left. In case of thread change, at edge 5, first thread I is kept bya pliers and cut, so that the thread end 12 of thread I is freed andprotrudes from edge 5 itself.

The insertion method provides that end 12 of thread I is caught first byan air current 22 that orients thread end 12 orthogonally to thestitches, preferably towards the above, and then by an air current 32that orients thread end 12, parallelly to course 2b before that knittingof course 3a by a thread II starts, in order to insert it completelybetween the stitches with respect to the edge 5. The knitting of course3a, from left to right, restrains the thread end 12 between course 3aand course 2b. Then, end 13 of thread II is freed and protrudes fromedge 5. Before knitting of course 4a starts, an air current 23 catchesthread end 13 and orients it according to its direction, orthogonally tothe stitches, and allows an air current 33 to catch it in turn and toalign it to course 3b, so that the knitting of course 4a with the samethread II restrains thread end 13 between course 3b and course 4a itself

In a similar way, as shown in FIG. 2, course 2b may belong to a collarand course 3a to another, and in this case end portions 12 and 13 aremade of the same thread, but are separated by one or more courses ofthread of union 1b and 1a, knitted with the interposition of idlestrokes of the carriage. In this case, only the thread end 13, as abovedescribed, must be restrained, whereas the thread end 12 must be leftfree because, in a second moment, is restrained in the stitches of thearticle to which the collar is stitched, after the separation of thecollars.

According to a preferred embodiment of the invention, for both the endportions of thread 12 and 13, in the case of FIG. 1, or only for threadend 13, in the case of FIG. 2, after the catching and inserting steps bymeans of currents 32 and 33 (or only 33), combing steps are provided forby means of a brush 29 that maintains the end portions themselvesaligned with the previous course of stitches waiting that it isrestrained by the next course.

In the case of FIG. 2, according to a preferred embodiment of themethod, the thread end 12 is located under the stitches by a sucking aircurrent 42, to prevent currents 23 and 33 from catching and restrainingit together to thread end 13 and causing the above described drawback.

With the method according to the present invention, therefore, theinsertion of thread ends 12 and 13 is carried out automatically in thecourse of knitting, with considerable advantage with respect to manualinserting and, in any case, with advantage with respect to themechanical insertion described above, since it is not necessary tointroduce a needle or other equivalent means between two successivecourses of stitches during knitting, which would cause a modification ofthe form of the knit article as described above.

With reference to FIGS. 3 and 4, a knitting machine of known type forthe production of collars and the like comprises a carriage 6a, slidingon a basement 6b, and two needle arrays 7. The machine also comprisesthread supports 8 sliding on guides 9 and whose stroke is limited by ablock 11 operated by pneumatic means 10. Every thread support 8, draggedselectively by carriage 6a, brings to the needles residing in the needlearray 7, by means of its end 8a which moves on a rectilinear trajectory8b, a thread of different color or of different quality and each freethread end is kept by pliers 14. In the passage from a type of thread tothe next, the thread support 8 having the previous thread withdraws an(ione of the pliers 14 grips it. Then, a cutter 15 cuts such threadleaving free one of the thread ends above described and indicated inFIG. 1 with 12 or 13.

According to a preferred embodiment of the invention, as shown in FIGS.3 and 4, a brush 29 is provided for operated by an actuator 30, whichcan translate integrally to carriage 6a. Brush 29, when pushed byactuator 30, can touch the stitches while knitting and substantially"comb" them, in particular stretching the thread end which lies on itwaiting to be restrained by the next course of stitches.

Always according to the invention, a restraining apparatus applicable toa knitting machine for collars comprises a blowing head 16, orientedhorizontally, and a nozzle 27 oriented vertically, also shown in FIGS. 3and 4. Head 16 and nozzle 27 are integral to a block 24, mounted on apneumatic actuator 25. As better shown in FIGS. 9, 10 and 11, head 16presents a central groove 17 and a couple of nozzles 18, parallel,oriented towards deflector 19. A tubular stem 20 brings compressed airfrom block 24 towards head 16.

With reference to FIGS. 5 and 6, the restraining step, in the case ofFIG. 1, is carried out as follows. Thread I, brought by a thread support8 and by which course 2b of the collar is being knitted, is kept stillby one of pliers 14 and is then cut by cutter 15, freeing a thread end12. At the same time of the cut, an air jet 22 coming from nozzle 27,which in this step is kept in a lowered position under the intersectionline 7a of the two needle arrays 7, creates an air current: directedupwardly which orients thread end 12 in a substantially verticaldirection. At the same time (FIG. 6), actuator 25 raises block 24 and,with it, head 16 and nozzle 27, which is continuing to blow and whichstops only when head 16 starts blowing emitting an air current 32. Thelatter current aligns thread end 12 with line 7a. Therefore, a secondthread support 28 starts knitting thread II and restrains thread end 12among the stitches. Actuator 25, in the meantime, lowers again in thefirst position of FIG. 5 and thread guide 28 can pass followingtrajectory 8b. Always with reference to FIG. 6, before that knitting ofcourse 3a starts, thread end 12 is aligned with the stitches but has notyet been restrained and is not necessarily stretched according to arectilinear shape, since jet air 32 has only oriented it in thatdirection. At that point, brush 29, pushed by actuator 30, lowers andcombs it. At the passage of thread guide 28, which knits course 3a whilebrush 29 is withdrawing, thread end 12 is eventually restrained andhidden among the stitches of the collar, without leaving portions orloops protruding from the edge.

As shown in FIG. 7, after that thread guide 28 has come back afterknitting the two courses of stitches, one forth 3a and one back 3b, endIla of thread II, kept by pliers 14b, is cut by cutter 15, freeing athread end 13. In a way similar to FIGS. 5 and 6, jet air 23, comingfrom nozzle 27, aligns vertically thread end 13. Therefore, air current33, coming from head 16, is emitted after that actuator 25 has raisedblock 24 and, with it, head 16 and nozzle 27, which was continuing toblow and which stops only when jet 33 starts blowing. Then, actuator 25lowers again and brush 29 repeats the above described movement, combingthread end 13. Thread support 28, then, starts knitting two furthercourses of stitches, one forth 4a and one back 4b, the formerrestraining thread end 13 which is hidden among the stitches of thecollar, without leaving portions or loops protruding from the edge.

With reference now to FIG. 8, in the case of FIG. 2, thread I brought bythread guide 8 and by which the first collar had been knitted up to thatpoint, is kept still from one of pliers 14 and is then cut by cutter 15freeing thread end 12. At the same time, an air jet 42 coming from head16, which at this step is under line 7a, produces an air current whichdrags thread end 12 under the needle arrays 7. Jet 42, in other words,produces a sucking current thanks to the lowered position of head 16. Atthis point, the thread of union is knitted, in the two courses 1a and1b, and then second thread support 28 starts knitting thread II andrestrains thread end 13 among the stitches, in the same way described inFIGS. 5 and 6 or 7. However, since the first courses of stitches knittedwith thread II are of tubular type, that is they are knittedalternatively with the needles of only one needle array at a time, morestrokes are required before that thread end 13 is restrained. Therefore,more passages of brush 29 are done since a course of stitches is knittedwith the needles of both the needle arrays thus restraining thread end13.

The particular shape of blowing head 16 and its possibility of movingvertically has the following advantages:

head 16 may remain lowered with respect to the needle arrays allowingthe passage of thread guide 8 without interference;

the thread can pass while knitting through groove 17, (FIGS. 9 and 11)without interference with blowing head 16 when this is in a raisedposition;

central groove 17 does not prevent head 16 from producing an effectiveblow thanks to the presence of eccentric nozzles 18 and of deflector 19(FIGS. 9, 10 and 11).

With reference to FIG. 12, cutter 15 can advantageously have a mobileblade 15a having an inclined upper profile 15b. A fixed blade 15c,Located underneath, has the task of cutting end 13 of thread IIa keptfrom the pliers 14b (FIG. 6). Inclined profile 15b has the task ofpreventing thread II, while brought by thread guide 28, from being cuttogether with thread end IIa, since it is effective to cut the latterwhen the carriage is on the left, in order to be able to start againknitting as soon as possible. In fact, owing to the differentinclination with respect to thread II, thread end Ila, when the mobileblade raises, overcomes profile 15b and locates on fixed blade 15c. Onthe other hand, thread II cannot exceed the profile 15b and keepsdistant from fixed blade 15c even when mobile blade lowers again forcutting thread end IIa. Since, while overcoming inclined profile 15b,thread end II would tend to loosen and therefore to be not cut by thecutter, a resilient hook 31 (FIGS. 6 and 7) is provided forre-establishing the stress of the thread end IIa after the overcoming ofinclined profile 15b.

As shown in FIG. 13, plate means can be provided for on the knittingmachine for preventing the thread end from being aligned outside theknitting line 7a comprised between the two needle arrays. Such platemeans can comprise two opposite plates 34 arranged laterally to theknitting line 7a, and/or a pusher 35 operated by a piston 36. Inparticular, plates 34 can be approached to line 7a before that head 16starts blowing air jets 32 or 33, whereas pusher 35 is operated afterevery passage of brush 29, in case the thread end would accidentallycome out from knitting line after stretching.

With reference now to FIGS. 14, 15, and 15A instead of head 16 raisingor lowering itself, along with first nozzle 27, a second nozzle 37 canbe provided lying on line 7a. In the former figure, second nozzle 37 isfixed, whereas in the latter figure second nozzle 37 is mobile and canrotate from a position A to a position B correspondingly directing theair jet 32 coming from it. In this way, the inserting step of the threadend occurs in the following manner. The first jet of air 22 coming outof nozzle 27 catches the end portion of thread aligning it with itselfas well as with the second jet of air 32 coming from nozzle 37 inposition A. Then second jet of air 37 turns from position A to positionB carrying with it the end portions of thread to align it with thecourse of stitches while knitting. In this way, there is nodiscontinuity in the passage from the hold of air jet 22 to the hold ofair jet 32 and a greater precision of insertion of the thread isobtained.

Reference is now made to FIGS. 16A, B and C, to describe the method forsimplifying the separation step of the collars. The collars 40, 41 and43 are kept attached to one another by a thread of union 1, which formsa loop 44 for each collar. When separating the collars, as shown in FIG.16A, according to the known art, the thread of union 1 must be cut at45, and then, by pulling the loops 44 in the direction of arrows 46, thethread of union unstitches easily and the collars remain alone. Sincethe cutting step of the thread of union at 45 is not easy to carry outautomatically, because if the cut occurs in a slightly differentposition, the collar can be damaged, according to the present inventionthe cutting step of the thread of union at 45 is carried out whileknitting, with the final result of FIG. 16B, freeing thread ends 45a and45b. In this way, the separation step does not require any cuttingoperation and is easier. However, to prevent the thread of union 1 frombeing pulled inadvertently during the finishing of the collars (dyeing,washing), ends 45a and 45b are restrained as shown in FIG. 16C in thesame way as described above. In this way, according to the invention,thread of union 1 can be pulled with a slightly stronger force than inthe case of FIG. 16B, but with the advantage of preventing ends 45a and45b from being pulled inadvertently.

Although reference has been made to jets of air for catching andinserting the end portions of thread, the successful use of jets ofwater has not been excluded, especially when the thread is particularlythick and heavy, in which case it would be necessary to use jets of airtoo powerful to control.

Furthermore, although reference has been made to fluid currentsaccomplished by mean:, of air or liquid jets, clearly it is equallypossible to accomplish the object of catching and orienting the endportions of thread by means of air currents created by suction.

What is claimed is:
 1. A knitting method for restraining, into stitches,an end portions of a cut thread protruding from an edge of a collar; themethod comprising:cutting said thread after knitting a first course ofstitches, creating a free thread end protruding from said edge; catchingsaid thread with a fluid current; aligning said thread end parallel tosaid first course of stitches via the fluid current; and stretching saidthread end onto said first course of stitches; and then knitting asecond course of stitches onto said first course of stitches.
 2. Themethod according to claim 1 including passage of a brush, wherein saidstretching step comprises lowering said brush onto said first course ofstitches, touching said first thread end, and combing said first threadend.
 3. The method according to claim 1 whereinsaid catching stepcomprises providing a first fluid current orthogonal to said firstcourse of stitches and wherein said alignment step comprises providing asecond fluid current parallel to said first course of stitches, saidsecond fluid current being provided by a mobile emitter, and aligningsaid mobile emitter to said first course of stitches only at a moment ofemission of said second fluid current.
 4. The method according to claim1, comprisingsucking said free end, which protrudes from said firstcourse of stitches, under said stitches via a fluid current.
 5. Themethod according to claim 4, comprising producing said sucking fluidcurrent via a mobile emitter located in a lowered position with respectto said first course of stitches.
 6. The method according to claim 1,comprisingseparating collars for knit wear articles, wherein the collarsare attached to one another by, a thread of union, the step ofseparating comprising cutting said thread of union forming two threadends which are restrained in turn among collar stitches of said collarvia said steps of catching, aligning, stretching and then knitting asecond course of stitches.
 7. A knitting apparatus applicable to aknitting machine for production of a collar, the apparatus being adaptedfor restraining an end portion of a cut thread protruding from an edgeof said collar into stitches making up the collar; the apparatuscomprising:a cutter adapted to a cutting of said end portion to form athread end; a fluid-current emitter adapted to catching and alignment ofsaid thread end with the stitches while knitting; and a brush adapted tocombing said end portion of thread parallel to said stitches whileknitting.
 8. The apparatus according to claim 7, wherein said means foremitting said fluid current comprises a blowing head directed parallelto said stitches and a nozzle directed orthogonally to said stitches,said head and said nozzle being mounted on an actuator that raises themor lowers them with respect to said stitches while knitting.
 9. Theapparatus according to claim 7, wherein said means for emitting saidfluid current comprises a first nozzle directed orthogonally to saidstitches and a second nozzle directed parallel to said stitches, saidsecond nozzle lying on the line of said stitches while knitting.
 10. Theapparatus according to claim 7, wherein said means for emitting saidfluid current comprises a first nozzle directed orthogonally to saidstitches and a second nozzle directed parallel to said stitches, saidsecond nozzle lying on the line of said stitches while knitting, saidsecond nozzle being mobile and adapted to rotate from a positionorthogonal to said stitches to a position parallel to said stitcheswhile knitting.
 11. The apparatus according to claim 7, wherein saidblowing head includes a central groove and a couple of eccentricparallel nozzles directed towards deflector means adapted to orient thefluid coming from said head parallel to said stitches while knitting.12. The apparatus according to claim 7, wherein said cutting meanscomprise a mobile blade and a fixed blade, said mobile blade beingplaced above said fixed blade and including an upper inclined profile.13. The apparatus according to claim 7, wherein plate means can beprovided for on said knitting machine for preventing said thread endfrom being aligned outside a knitting line.